Answer:
Friction depends on the coefficient of friction which in turn depends upon the nature of the surface. Hence, this statement
is false.
The synthesis of diphenylacetylene from mesostilbene dibromide includes next reactions:
• Bromination of stilbene-it is the reaction of electrophilic adition and bromonium ion is formed as intermedier (meso compound is the product).
• Bimolecular elimination-strong base is used in this reaction (takes away the H) and pi bond is formed.
Answer:
The correct answer is option - e. all of the above are useful traits.
Explanation:
A cloning vector is a small segment of DNA that can be established stably in an individual organism and able to internalize a foreign DNA for cloning purposes. The cloning vector could be taken from different organisms such as plasmid of a bacterium, or DNA from a virus. A cloning vector must possess some characteristics -
The cloning vector must be self-replicating ability in the host cells, it should be small in size with restriction site for the restriction endonuclease enzymes in it. The replication character of the vector should not interfere with the internalized DNA fragment. The presence of marker genes in the vector is also a property that is helpful in identifying of recombinant cells.
Thus, the correct answer is option - e. all of the above are useful traits.